40 citations · 97 across the 17 of their papers we have counts for
18 papers
Vanishing Love Numbers of Kerr-Newman Black Holes
Sumanta Chakraborty, Takuya Katagiri, Paolo Pani +1
Tidal Love numbers characterize the conservative response of compact objects to external perturbations and provide a powerful probe of their nature. While the static Love numbers o…
Tidally-enhanced resonances in extreme-mass-ratio inspirals: A tertiary path to chaos
Kyriakos Destounis, Takuya Katagiri, Sajal Mukherjee +1
Extreme-mass-ratio inspirals (EMRIs) provide a unique laboratory for probing strong-field gravity and complex relativistic dynamics. We study a tidally deformed EMRI composed of a…
New Universal Relations for Magnetized Neutron Stars
Byon N. Jayawiguna, Siddarth Ajith, Takuya Katagiri +2
Unlike the neutron-star mass--radius relation, which depends sensitively on the internal stellar structure through the equation of state of dense nuclear matter, certain neutron-st…
Out-of-Equilibrium Effects in Non-Radial Relativistic Stellar Perturbations: A Model-Agnostic Formulation and Mode Analysis
Takuya Katagiri, Victor Guedes, Kent Yagi
We present a systematic, model-agnostic analysis of out-of-equilibrium effects, including viscosity and thermal conductivity, in non-radial oscillations of relativistic stars. Exte…
Dynamical tidal response of neutron stars: From effective field theory to gravitational waveforms
Thomas Apostolidis, Valerio De Luca, Leonardo Gualtieri +3
We investigate the fully relativistic dynamical tidal response of neutron stars up to second order in the frequency. Combining the worldline effective field theory for extended gra…
The relativistic restricted three-body problem: geometry and motion around tidally perturbed black holes
Takuya Katagiri, Vitor Cardoso
We investigate the geometry of a tidally deformed, rotating black hole and timelike geodesics in its vicinity. Our framework provides a local picture of the structural evolution of…
Theoretical modeling of approximate universality of tidally deformed neutron stars
Takuya Katagiri, Gowtham Rishi Mukkamala, Kent Yagi
Quasi-universal relations are known to exist among various neutron star observables that do not depend sensitively on the underlying nuclear matter equations of state. For example,…
Tidal response beyond vacuum General Relativity with a canonical definition
Takuya Katagiri, Vitor Cardoso, Tact Ikeda +1
Tidal effects on compact objects provide profound theoretical insights into the structure of the field equations, and are wonderful probes of the equation of state of matter, the n…
On relativistic dynamical tides: subtleties and calibration
Takuya Katagiri, Kent Yagi, Vitor Cardoso
The response of astrophysical compact objects to external tidal fields carries valuable information on the nature of these objects, on the equation of state of matter, and on the u…
Hushing black holes: tails in dynamical spacetimes
Vitor Cardoso, Gregorio Carullo, Marina De Amicis +6
Stationary, asymptotically flat, black hole solutions of the vacuum field equations of General Relativity belong to the Kerr family. But how does one approach this state, dynamical…
Parametrized Love numbers of non-rotating black holes
Takuya Katagiri, Tact Ikeda, Vitor Cardoso
A set of tidal Love numbers quantifies tidal deformation of compact objects and is a detectable imprint in gravitational waves from inspiralling binary systems. The measurement of…
Stability of relativistic tidal response against small potential modification
Takuya Katagiri, Hiroyuki Nakano, Kazuyuki Omukai
The tidal response of compact objects in an inspiraling binary system is measured by a set of tidal Love and dissipation numbers imprinted in the gravitational waveforms. While a f…
Hairy black holes in AdS with Robin boundary conditions
Tomohiro Harada, Takaaki Ishii, Takuya Katagiri +1
We study hairy black holes in Einstein-Maxwell-complex scalar theory in four-dimensional asymptotically global anti-de Sitter (AdS) spacetime when the Robin boundary conditions are…
Vanishing Love of Black Holes in General Relativity: From Spacetime Conformal Symmetry of a Two-dimensional Reduced Geometry
Takuya Katagiri, Masashi Kimura, Hiroyuki Nakano +1
We study the underlying structure of the vanishing of the Love numbers of both Schwarzschild and Kerr black holes in terms of spacetime conformal symmetry in a unified manner for t…
Ladder operators and quasinormal modes in Bañados-Teitelboim-Zanelli black holes
Takuya Katagiri, Masashi Kimura
We study quasinormal modes (QNMs) of massive Klein-Gordon fields in static Bañados-Teitelboim-Zanelli (BTZ) black holes in terms of ladder operators constructed from spacetime conf…
The Aretakis constants and instability in general spherically symmetric extremal black hole spacetimes: higher multipole modes, late-time tails, and geometrical meanings
Takuya Katagiri, Masashi Kimura
We study late-time behaviors of massive scalar fields in general static and spherically symmetric extremal black hole spacetimes in arbitrary dimensions. We show the existence of c…
Revisiting the Aretakis constants and instability in two-dimensional Anti-de Sitter spacetimes
Takuya Katagiri, Masashi Kimura
We discuss dynamics of massive Klein-Gordon fields in two-dimensional Anti-de Sitter spacetimes (), in particular conserved quantities and non-modal instability on the futur…
Stability of small charged anti-de Sitter black holes in the Robin boundary
Takuya Katagiri, Tomohiro Harada
We analytically and numerically study quasinormal frequencies (QNFs) of neutral and charged scalar fields in the charged anti-de Sitter (AdS) black holes and discuss the stability…